A rocker shaft for oiling engine components includes an outer tube and an insert extending through the outer tube. The insert defines a plurality of lumens. Each of the plurality of lumens extends through the insert and is configured to receive oil from an oil pump. An engine system includes a cylinder block, a cylinder head connected to the cylinder block, an overhead structure connected to the cylinder head, and a rocker shaft connected to the overhead structure such that a first end of a rocker arm connected to the rocker shaft is positioned above a cylinder of the cylinder block. A method of manufacturing the rocker shaft includes providing an outer tube and an insert, placing the insert in the outer tube, and aligning each of a plurality of lumens defined by the insert with a plurality of outer oil holes defined by the outer tube.

A rocker shaft for oiling engine components includes an outer tube and an insert extending through the outer tube. The insert defines a plurality of lumens. Each of the plurality of lumens extends through the insert and is configured to receive oil from an oil pump. An engine system includes a cylinder block, a cylinder head connected to the cylinder block, an overhead structure connected to the cylinder head, and a rocker shaft connected to the overhead structure such that a first end of a rocker arm connected to the rocker shaft is positioned above a cylinder of the cylinder block. A method of manufacturing the rocker shaft includes providing an outer tube and an insert, placing the insert in the outer tube, and aligning each of a plurality of lumens defined by the insert with a plurality of outer oil holes defined by the outer tube.

An engine brake rocker arm assembly is operable in an engine drive mode and an engine braking mode and selectively opens first and second exhaust valves. The engine brake rocker arm assembly includes an exhaust rocker arm configured to rotate about a rocker shaft, an engine brake capsule assembly movable between (i) a locked position configured to perform an engine braking operation, and (ii) an unlocked position that does not perform the engine braking operation, and a hydraulically controlled actuator assembly configured to selectively move the engine brake capsule assembly between the first and second positions.

An engine brake rocker arm assembly is operable in an engine drive mode and an engine braking mode and selectively opens first and second exhaust valves. The engine brake rocker arm assembly includes an exhaust rocker arm configured to rotate about a rocker shaft, an engine brake capsule assembly movable between (i) a locked position configured to perform an engine braking operation, and (ii) an unlocked position that does not perform the engine braking operation, and a hydraulically controlled actuator assembly configured to selectively move the engine brake capsule assembly between the first and second positions.

Methods and systems are provided for providing compression release during a stop/start event in an engine. In one example, a method includes: responsive to a request for a stop/start event in an engine with a continuously variable valve lift (CVVL) system including a compression release hydraulic valve actuator coupled to a valve of a first cylinder, determining a desired stop position of the engine; and prior to restarting the engine during the stop/start event, adjusting the compression release hydraulic valve actuator to open the valve during a compression stroke of the first cylinder. In this way, an amount of torque used to restart the engine may be reduced.

Methods and systems are provided for providing compression release during a stop/start event in an engine. In one example, a method includes: responsive to a request for a stop/start event in an engine with a continuously variable valve lift (CVVL) system including a compression release hydraulic valve actuator coupled to a valve of a first cylinder, determining a desired stop position of the engine; and prior to restarting the engine during the stop/start event, adjusting the compression release hydraulic valve actuator to open the valve during a compression stroke of the first cylinder. In this way, an amount of torque used to restart the engine may be reduced.

A rocker shaft assembly configured to support a rocker arm and deliver oil to the rocker arm and related method of making is provided. The rocker shaft assembly includes a core shaft and a sleeve. The core shaft has a core body including a main oil supply channel formed thereon. The sleeve has passages formed thereon. The sleeve is disposed around the core shaft. The main oil supply channel aligns with at least one of the passages on the sleeve. The main oil supply is milled into the core shaft.

A rocker shaft assembly configured to support a rocker arm and deliver oil to the rocker arm and related method of making is provided. The rocker shaft assembly includes a core shaft and a sleeve. The core shaft has a core body including a main oil supply channel formed thereon. The sleeve has passages formed thereon. The sleeve is disposed around the core shaft. The main oil supply channel aligns with at least one of the passages on the sleeve. The main oil supply is milled into the core shaft.

An engine includes at least one cylinder, a first intake valve and a second intake valve associated with the cylinder, to control a flow of intake air from a first intake duct and a second intake duct, respectively. The two intake ducts communicate with a common intake manifold, so as to receive air at the same pressure. During the intake stage, in each cylinder operating cycle, initially an opening and closing movement of only the first intake valve is activated, while the second intake valve remains closed and, subsequently, an opening and closing movement of only said second intake valve is activated, while the first intake valve remains closed. In this way, the two air flows at the same pressure entering the cylinder give rise to a high turbulent kinetic energy, to the advantage of combustion efficiency and reduction of harmful exhaust emissions.

An engine includes at least one cylinder, a first intake valve and a second intake valve associated with the cylinder, to control a flow of intake air from a first intake duct and a second intake duct, respectively. The two intake ducts communicate with a common intake manifold, so as to receive air at the same pressure. During the intake stage, in each cylinder operating cycle, initially an opening and closing movement of only the first intake valve is activated, while the second intake valve remains closed and, subsequently, an opening and closing movement of only said second intake valve is activated, while the first intake valve remains closed. In this way, the two air flows at the same pressure entering the cylinder give rise to a high turbulent kinetic energy, to the advantage of combustion efficiency and reduction of harmful exhaust emissions.